An experimental investigation on heat transfer to the ceiling of the riser of circulating fluidized bed

To understand the heat transfer mechanism to the ceiling of a circulating fluidized bed (CFB) riser, experiments were conducted at four different superficial gas velocities and three external solid circulation rates in a CFB pilot plant with a riser having a height of 5 (m) and a cross section of 1.0 (m) x 0.5 (m). The experiments suggested that both solid circulation rates and superficial gas velocities had significant influence on the local heat transfer to the ceiling at the riser exit to the gas solid separator. However, on the opposite of the exit, solid circulation rates and superficial gas velocities had only a minor influence on the local heat transfer coefficients to the ceiling.